Alkyd and acrylic paints are some of the most common types of paints when it comes to serious painting works: painting walls, metal products etc. Perhaps due to the similarity of the name, they are often confused. Do these types of paints really have anything in common?
Compound
In fact, the only similarity is that both are paints. They are completely different in composition.
Alkyd type can be called a more modernized option oil paints. They are characterized by a similar mechanism of hardening and formation of a surface film (which, by the way, is somewhat stronger, but less elastic). Consist alkyd paints from polyhydric alcohols (for example, glycerin) in combination with orthophthalic acid. Actually, the word “alkyd” comes from a combination of the words “alcohol” (alcohol) and “acid” (acid).
Unlike alkyd paints, acrylic paints are made on the basis of acrylic, a polymer better known as plexiglass. Paints may contain various additional components designed to improve certain properties (add elasticity, speed up drying).
Basic properties
- Life time. Unlike alkyd paint, the surface of acrylic paint retains its original appearance much longer. It is advisable to renew alkyd paint about once a year, since oxygen and ultraviolet radiation intensively destroy the surface layer of paint. Acrylic coating, subject to surface preparation and paint application technology, can last from 8 (wood) to 20 (plaster) years.
- UV resistance. Acrylic practically does not change the properties of the surface film when exposed to sunlight, that is, it does not fade, does not turn yellow, and does not acquire a “matte” appearance. Alkyd compounds are not so reliable in this regard.
- Drying process. But the alkyd film dries relatively quickly, and after just a couple of days it fully fulfills its protective and decorative functions. The acrylic film completes its formation approximately a month after application to the surface. In this case, the coating should be protected from mechanical influences until it is completely dry.
- Mechanical stability. The longer process of forming the acrylic film is compensated by more high level resistance to mechanical stress (deformation, scratches).
- Decorative properties.
8. Is it possible to apply acrylic paint to alkyd paint and vice versa?
Alkyd compositions are distinguished by a more diverse range of shades and undertones, as well as generally more bright colors. On the other side, acrylic paint lasts longer and does not require regular updating.
Are acrylic and alkyd paints compatible?
Is it possible to apply alkyd compounds to acrylic or vice versa? Neither of these is recommended, especially if the substrate was painted relatively recently or if the surface is metal. The fact is that the specific composition of the paints may not be completely clear to us. Alkyd compositions may contain components that will appear as dark spots through the acrylic paint layer. If alkyd paint is applied over acrylic, then it may not adhere to it, that is, it may peel off.
The only option for applying such paints to each other is to apply it to an old coating from which all the volatile components have already evaporated. However, even in this case, apply the top coat of paint only after treating the surface with a similar type of primer (that is, acrylic paint on acrylic primer and vice versa).
Acrylic and oil paints are used for finishing surfaces from the outside, as well as inside. In some cases, it is necessary to cover with acrylic a surface that has been painted with oil paint. To find out whether one paint can be coated with another, you need to consider the properties of each material.
Oil paint
Some time ago, oil paints were actively used to decorate surfaces inside and outside. But they were replaced by a new, more universal material, acrylic paints.
The oil material is made from drying oil or a similar product, which is mixed with pigments mineral type. The paint is obtained by grinding all components to a homogeneous composition. IN modern renovation oil paint is used very rarely. But in some cases it is advisable to use it as a cost-saving option for painting large rooms, since its cost is lower than other materials. The main advantage of oil-based paints is their low cost. Such materials are resistant to moisture, oils have reliable protection wooden, and concrete materials. Oil-based paints also prevent rust on metal surfaces.
This material has its drawbacks, which makes working with paint not very convenient. There are not too many colors, almost a dozen, so it is difficult to create a specific design and give originality to the surface.
Also, the paint needs to be renewed annually, that is, it wears out quickly, which requires additional costs. If the surface is not renewed in a timely manner, the material may peel off in large pieces. Appears during application strong smell, so work is performed in a well-ventilated area. When dry, the surface releases toxic elements, so it is best not to spend time in a painted room. A negative quality is the long drying time of such material, almost two days.
You can apply acrylic paint to an oil surface; this will not be difficult.
Acrylic paints
Compared to oil compositions, acrylic paints have clear advantages. Acrylic compositions are environmentally friendly and do not emit toxic substances, since they do not contain organic solvents.
The basis of this material is water, due to this there is practically no odor during application. The material also has a large number of colors and shades, this allows you to make the surface original. Required color You can order it from a hardware store, and it will be made on site. The acrylic composition has high stability to humidity, ultraviolet rays, and temperature changes, and also has good vapor permeability. Thus, acrylic paint is used to decorate the room inside and outside. The painted surface dries quickly, in just a couple of hours. If we compare oil- and acrylic-based paints, the latter are considered more durable and wear-resistant. Such compositions are considered universal and are used to create a variety of interiors.
Can you paint with acrylic paint over oil paint?
Typically, experts do not recommend applying acrylic paint to something that is too old. oil coating, since the materials do not adhere well to each other. But such work is allowed provided that the surface is thoroughly prepared. Surface preparation work begins with sanding the previous coating, using fine-grained sandpaper.
After grinding, the surface is thoroughly cleaned of dirt and dust that has formed as a result of work; a vacuum cleaner can be used for this. Then the surface is degreased and left to dry. The dry surface is covered with 2 layers of acrylic-based solution. But thorough preparatory work don't talk about high-quality application acrylic paint on an oil surface. To get the result, you must use a thick acrylic composition; when diluted with water, the proportions should not exceed 1 to 1.
If a spray bottle is used as the application tool, a suitable thinner must be added. The gloss or dullness of the surface depends on the type of this substance. Sometimes oil paint eats into the surface, especially if it is used too much. long time, then it is impossible to remove it. In this case, special paints are used that are characterized by high adhesion; they are able to efficiently paint even a very greasy surface.
Technology of applying acrylic paint based on oil composition
- First, the surface is sanded, all dust is removed using a vacuum cleaner.
- Then they are treated with a primer. And leave until completely dry.
- The acrylic composition is applied with a brush or spray; in the latter case, special thinners are used.
- Start applying paint from the corners of the surface to the middle or from top to bottom. After full coverage walls or ceiling, leave time to dry, usually a couple of hours; there are paints that dry faster.
Basic rules when applying acrylic paint to an oil composition
- To ensure a high-quality painted surface, it must be well prepared. The main oil layer of paint is removed by sanding, and then the dust is removed.
- All dirt must be cleaned off so that the acrylic composition lays down in an even layer.
The difference between alkyd paint and acrylic paint
- In too advanced cases. If oil has become embedded in a wooden or other surface, use special paints with a high adhesion rate.
- Surface grinding can be done sandpaper with fine grain or special grinder. In some cases, a drill and a special attachment are used; you must act carefully so as not to damage the surface.
- Degreasing is a mandatory step, otherwise the new composition will not adhere well to the old surface.
- To ensure high-quality adhesion of the paint to the previous surface, the acrylic composition must have a thick consistency.
When choosing a paint composition, it is necessary to study its properties, all positive and negative qualities, since the service life of the coating and its reliability depend on this. Before purchasing material, you need to consider what kind of coloring will be done, primary or secondary. In the second option, a surface that has already been previously treated with other compounds is coated.
It is especially taken into account when the walls are painted with oil paint, these are the consequences of old repairs. Typically, oil paint was used for kitchens or bathrooms. When choosing a modern acrylic-based paint, you need to figure out what to do with the old finish, namely the oil composition. This article describes all the advantages and disadvantages of oil and acrylic paints.
It is usually not recommended to coat oil paint with an acrylic composition, but it is possible if you resort to careful surface preparation. The old material is partially cleaned off by sanding with sandpaper, primed, and covered with acrylic paint.
Alkyd primer and acrylic paint
A primer is applied to the surface before painting to provide protection to the surface and to improve the adhesion of the paint that will be applied over the primer. The deeper the soil penetrates into the treated surface, the better later the paint will stick to it. A primer for metal, for example, is a prerequisite for high-quality painting of metal surfaces.
When applied, the primer fills the pores of the surface and binds small particles of foreign matter (for example, dust), thereby preparing it for the application of paint or other paints and varnishes.
What is the difference between alkyd paint and acrylic paint?
Any primer, be it an acrylic primer for wallpaper or a primer composition for metal, can significantly reduce consumption expensive materials. The savings are especially noticeable when priming large areas.
Another advantage of using a primer is that the primer material slows down the penetration of substances from the composition of the next layer, which helps to dry the painted surface evenly. Uniform drying, in turn, improves the quality of painting, eliminating cracks and warping on the surface being treated.
Currently the lineups of this type, whether it is a water-dispersion primer or primer deep penetration, are indispensable materials for interior or exterior renovation of residential buildings and production premises. There are many types of primer coatings (acrylic wood primer, alkyd primers, strengthening and binding compounds, materials for priming metals) intended for different types surfaces and materials of subsequent layers.
Substances included in the primer coating should not react with substances from paints and varnishes that will be applied over the primer. Therefore, before starting repairs, it is necessary to find out what type of primer is suitable for a particular paint and surface. For example, a deep-penetrating universal acrylic primer works well on plaster, brick or concrete. Putty, plaster and other finishing materials will subsequently work well on compositions of this type.
Primer compounds are also useful if you need to treat a loose, crumbling surface. For repair work With such surfaces, deep penetration compounds have been developed that can make the surface denser and prepare it for painting or finishing. The cost of deep penetration primer is quite high, but for high-quality repairs it is sometimes irreplaceable.
If you are going to carry out renovations in a room that differs high humidity, then pay attention to such a material as the universal acrylic primer Bulls Eye 1-2-3 Primer Sealer Stain-Killer. This coating contains antiseptics that prevent the spread of mold and fungi. This acrylic primer is perfect for treating surfaces made of various materials - concrete, brick, plasterboard, chipboard, wood, metal and many others.
Alkyd and acrylic paints are some of the most common types of paints when it comes to serious painting projects: painting walls, metalwork, etc. Perhaps due to the similarity of the name, they are often confused. Do these types of paints really have anything in common?
Compound
In fact, the only similarity is that both are paints. They are completely different in composition.
The alkyd type can be called a more modernized version of oil paints. They are characterized by a similar mechanism of hardening and formation of a surface film (which, by the way, is somewhat stronger, but less elastic). Alkyd paints consist of polyhydric alcohols (for example, glycerin) in combination with orthophthalic acid. Actually, the word “alkyd” comes from a combination of the words “alcohol” (alcohol) and “acid” (acid).
Unlike alkyd paints, acrylic paints are made on the basis of acrylic, a polymer better known as plexiglass. Paints may contain various additional components designed to improve certain properties (add elasticity, speed up drying).
Basic properties
- Life time. Unlike alkyd paint, the surface of acrylic paint retains its original appearance much longer. It is advisable to renew alkyd paint about once a year, since oxygen and ultraviolet radiation intensively destroy the surface layer of paint. Acrylic coating, subject to surface preparation and paint application technology, can last from 8 (wood) to 20 (plaster) years.
- UV resistance. Acrylic practically does not change the properties of the surface film when exposed to sunlight, that is, it does not fade, does not turn yellow, and does not acquire a “matte” appearance. Alkyd compounds are not so reliable in this regard.
- Drying process. But the alkyd film dries relatively quickly, and after just a couple of days it fully performs its protective and decorative functions. The acrylic film completes its formation approximately a month after application to the surface. In this case, the coating should be protected from mechanical influences until it is completely dry.
- Mechanical stability. The longer process of forming an acrylic film is compensated by a higher level of resistance to mechanical stress (deformation, scratches).
- Decorative properties. Alkyd compositions are distinguished by a more diverse range of shades and halftones, as well as generally brighter colors. On the other hand, acrylic paint lasts longer and does not require regular updating.
Are acrylic and alkyd paints compatible?
Is it possible to apply alkyd compounds to acrylic or vice versa? Neither of these is recommended, especially if the substrate was painted relatively recently or if the surface is metal. The fact is that the specific composition of the paints may not be completely clear to us. Alkyd compositions may contain components that will appear as dark spots through the acrylic paint layer. If alkyd paint is applied over acrylic, then it may not adhere to it, that is, it may peel off.
The only option for applying such paints to each other is to apply it to an old coating from which all the volatile components have already evaporated. However, even in this case, apply the top coat of paint only after treating the surface with a similar type of primer (that is, acrylic paint on acrylic primer and vice versa).
There are several types of acrylic paints:
a) acrylic paints on water based(interior or facade paints);
b) two-component acrylic enamels (car acrylic paints in a can).
They contain two components: paint and hardener; they polymerize due to a chemical reaction with the hardener, and this reaction is irreversible.
c) one-component acrylic enamels (used in aerosols). They dry in air due to the evaporation of solvents.
Acrylic two-component paints cannot be applied to alkyd and acrylic one-component paints, as they behave aggressively towards the latter. It is possible to apply alkyd and one-component acrylic paints to two-component paints, since the polymerization reaction is irreversible and the coating is durable.
Aerosol paints use a one-component base.
All aerosols dry in air due to the evaporation of solvents. Therefore, combine the application of acrylic and alkyd ones on top of each other. aerosol paints Maybe. But you need to apply the paint no later than 30 minutes after applying the last layer of paint (acrylic or alkyd).
8. Is it possible to apply acrylic paint to alkyd paint and vice versa?
Also, the solvent plays an important role. If the solvent is aggressive, it can dissolve alkyd paint. Typically, more aggressive solvents are found in acrylic one-component paints. Therefore, when applying acrylic one-component paint over alkyd paint, you need to be careful and first make sure that the coating is not adversely affected.
In the case of applying alkyd one-component paint to acrylic, subject to temporary recommendations (no later than 30 minutes after applying the last layer of paint), there is no reason to be afraid, since solvents in alkyd one-component paints are less aggressive.
Repairing painted surfaces is an inevitable process. Even if the finishing was previously done competently and with high-quality materials.
Before repainting the walls, you need to make sure that the new and old coating will be compatible.
At the moment, there are many ways to remove old paint.
- Mechanical methods. Acrylic enamel and acrylic paint or other coating is removed with sharp objects or power tools, for example, a drill with an attachment.
- Thermal methods. In this case, the paint softens, for example, construction hairdryer, and then deleted.
- Chemical methods. The finish is removed using a variety of removers.
However, the process of removing the old coating is long and labor-intensive. And the price of the issue is quite high, especially if you need to remove paint from large area or complex surfaces. Based on this, many of us prefer to apply a new finish directly to the old one. In this case, the question of compatibility of coatings often arises.
In this article we will talk about whether acrylic paint can be applied to enamel and vice versa. However, first we will understand the basic concepts.
Types of paints and varnishes
The composition of paints and varnishes includes binders, fillers, pigments, solvents/thinners and additives. In order to competently use paint and varnish materials during repairs, you need to know exactly their composition.
Main Components
Oil paints based on drying oil.
All paints are divided according to the type of binder used and the type of solvent.
- The binder determines the main qualities of the paint, the service life of the coating and the speed of its drying. There are 4 common types of binders used for paints and varnishes: alkyd and epoxy resins, oil-based (on drying oil), latex, acrylic polymers.
- Solvent components are divided into solvents and diluents.. The former reduce the fluidity and viscosity of the material. Thinners only reduce the viscosity of the paint.
- To improve the characteristics of paints and varnishes, additives are added to their composition.: stabilizers, emulsifiers, fungicides, antiseptics, etc.
- Special paints belong to a separate category. These are anti-corrosion coatings, for example, Zinga electrically conductive paint. Analogs with antiseptic properties that protect the base from mold and rot. Compositions for removing small defects (irregularities, scratches, cracks), etc.
Oil and enamel compositions
The photo shows acrylic enamel.
For materials based on alkyd and acrylic resins include oil and enamel paints.
They are suitable for painting metal, wood and plastered surfaces.
After drying, they are non-toxic, light and moisture resistant.
- Oil paints are produced on the basis of drying oil. White Spirit, gasoline, turpentine or solvent naphtha are used as diluents. The compositions are not expensive, but they take a long time (up to several days) to dry. The main disadvantage is that the coating turns yellow over time.
- In enamel compositions, like binder, varnish is added. It gives the coating gloss and aesthetics. The instructions recommend using such paints for external and internal finishing works for metal, wood, concrete, plaster.
Differences between alkyd and acrylic paints
Enamels are moisture and light resistant. They also have anti-corrosion resistance.
Emulsion and dispersion materials
Water-dispersed composition.
Such paints are diluted, but not soluble with water. In them, the binder and pigment particles are distributed in a liquid medium, creating a stable emulsion.
When the coating dries, it is not washed away by water.
- Emulsion compositions are economical, environmentally friendly and fire safe.
- They fit well on almost any substrate.
- They dry quickly and do not have a pungent odor.
Many people think that water-based and water-dispersion formulations are the same.
However, they are different.
- Matte emulsions wash off over time. The dispersions are waterproof and suitable for use in damp areas.
- Water-dispersion compositions are usually white; water-based analogues have a variety of colors.
- Dispersions cannot be used at temperatures below +5 degrees. However, with the addition of modifiers, they are thermally stable. Such, for example, are fire-retardant paints for metal Polistil.
Note!
The best analogues from water-based paints - based on acrylic resins and polymers.
They have high elasticity and strength.
- Such compositions are frost-resistant after they are completely dry.
- They are vapor permeable.
- Suitable for alkaline substrates (concrete, plaster).
- These paints are tinted very well.
- Resistant to ultraviolet radiation, retains its original color for a long time.
- They have the ability to repel water.
- They have high mechanical stability.
About paint compatibility
First, you need to apply epoxy putty to the old coating.
Based on everything written above, we will answer main question article - is it possible to paint on enamel with acrylic paint and vice versa.
- Based on their composition, acrylic paints and varnishes can only be applied to the same old coating. They cannot be applied over alkyd enamels due to incompatibility of thinners/solvents. The new coating will simply curl (raise) the enamel.
- In addition, it is not advisable to apply emulsion and dispersion compositions to old glossy and adhesive paints. The same applies to varnished bases.
- But after emulsion and dispersion materials, you can use any enamels and paints.
Now let’s talk about how to apply a coating of acrylic paint with your own hands without removing the enamel.
Note!
To do this, you need to create an intermediate layer that is resistant to both acrylic and organic solvents in a stable state.
It should consist of polyesters (for example, epoxy resin, polyurethane) with amine hardeners.
Such compounds are dissolved with acetone.
After puttying, acrylic primer is applied.
Nowadays many liquid putties and primers with the described composition are sold.
One of the best materials is "Inter Troton Spray".
- First, apply liquid putty over the enamel.
- Next, cover the surface with acrylic primer.
- Then you can paint the base.
Conclusion
If you are unable to withdraw old paint, then a new coating can be applied to it. However, there are nuances here. Some types of paints and varnishes are incompatible, so between them it is necessary to create an intermediate layer of neutral compounds. By watching the video in this article, you will expand your knowledge base.
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Alkyd or acrylic primer: which one to choose?
Surface preparation before finishing with any materials is extremely important. Priming helps save you money, significantly improve the quality of your repair and extend its service life. How to choose the right building materials and perform the work?
The primer is used for all types of substrates: metal, wood, concrete, brick, plaster, drywall, putty. Its main purpose is to provide a strong “grip” finishing materials, be it wallpaper, paint, varnish or tile, with a base. Paint and varnish technologies do not stand still, now you can find a primer that will protect wood from rotting and fungus formation, metal from corrosion, give plaster or putty special strength due to deep penetration or even color.
The choice of primer should be based on the type of substrate and the properties you want to give it. Available on store shelves today a large assortment acrylic and alkyd materials.
What is the difference between alkyd paint and acrylic paint?
The former are used for almost any reason. Their main advantage is that they are odorless. When renovating small spaces, acrylic primer is indispensable. However, if you need to carry out metal work, then only alkyd material. It reliably protects iron from rust. Experienced builders prefer alkyd primers to acrylic ones for outdoor work.
The most common alkyd primer is GF-021. Its anti-corrosion properties can significantly extend the service life of metal products. In addition, the primer is often and successfully used for other types of substrates, for example, wood, drywall, brick, plaster. Specifications, which manufacturers indicate on the labels, give the right to call the GF-021 primer universal. In particular, on the bank trademark“Yaroslavl flavor” is what this term means. If you are in doubt about which primer to buy, then you can safely choose GF-021 primer. Technical characteristics, including consumption per 1 m2 and drying time, vary across all product lines. Before purchasing, be sure to read the instructions for use.
Traditional colors for alkyd primer are brown, red-brown and gray. The palette of this material is not always of great importance, since most often it is applied under finishing materials. As the primer absorbs and dries, it becomes dull, but can affect the color of the future coating. If you choose a primer for light-colored wallpaper, then alkyd will not suit you.
Among acrylic materials, deep penetration primers stand out. They are designed to strengthen loose and fragile foundations. These may include concrete, plaster, wood, cement, gypsum, plasterboard, and previously painted surfaces. This type of primer penetrates as deeply as possible into the base and reduces its absorption capacity, allowing significant savings on subsequent painting work. You will find such soil in the “Yaroslavl Color” and “Norma” lines.
The Braska line also includes a deep penetration primer, but it has additional properties that are valuable for repairs. It contains a fungicide - a chemical substance to combat fungal diseases. The primer is ideal for woodworking, protecting the base from the formation of mold and harmful bacteria.
Acrylic primers, unlike alkyd ones, are colorless, some of them are used as an independent coating. This is your option if you are looking for a primer for gluing light-colored wallpaper. This type of primer can be used both indoors and outdoors.
You don’t have to worry about the quality of the coating formed by the primer if you choose it taking into account the existing base and finishing materials. In this case, the soil will responsibly fulfill all the duties assigned to it.
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Alkyd primer is an excellent analogue of imported primer. It can be used in cases where the surface to be treated does not need to be pre-impregnated.
Advantages of alkyd primer.
— high soil strength;
- resistant to abrasion after drying;
— reliably covers resinous knots. They are not visible even after several years;
— any paints (acrylic, alkyd, enamel, latex and nitro paint), glue (wallpaper, universal, PVA) and putties (acrylate and acrylic) lie smoothly on it;
— in addition to metal surfaces, alkyd primer is suitable for priming wood, plastic, plaster, laminated surfaces, chipboard, fiberboard, concrete, as well as surfaces previously painted with any paint;
- can be used when negative temperature;
- low toxic chemical composition. Can work without using special means protection, it is enough that the room is simply well ventilated;
— you can dilute the alkyd primer or clean the surface from it using white spirit. Inexpensive and accessible chemical.
Disadvantages of alkyd primer.
- long drying period;
— if the alkyd primer has not dried completely, some paints may curl upon contact with it;
- only the upper part of the surface is processed. That is, the alkyd primer does not penetrate deep into the material and cannot be used as a fixative for crumbling and loose materials. For them it is necessary to use acrylic primers;
- construction bandage from synthetic material that are not completely bonded to the surface should not be wetted with an alkyd primer. Because the bandage will bubble and stretch;
— despite the fact that white spirit is not a highly toxic substance, it is still quite harmful.
Is it possible to apply alkyd paint over acrylic primer?
Therefore, until the alkyd primer dries completely, the room must be well ventilated;
— the tools used for priming (brush or roller) must be stored wrapped in a rag moistened with white spirit. To prevent air from entering, they are additionally wrapped in polyethylene. This way the tools can be stored for a week. Then they can only be cleaned with special means.
Alkyd and acrylic paints are some of the most common types of paints when it comes to serious painting projects: painting walls, metalwork, etc. Perhaps due to the similarity of the name, they are often confused. Do these types of paints really have anything in common?
Compound
In fact, the only similarity is that both are paints. They are completely different in composition.
The alkyd type can be called a more modernized version of oil paints. They are characterized by a similar mechanism of hardening and formation of a surface film (which, by the way, is somewhat stronger, but less elastic). Alkyd paints consist of polyhydric alcohols (for example, glycerin) in combination with orthophthalic acid. Actually, the word “alkyd” comes from a combination of the words “alcohol” (alcohol) and “acid” (acid).
Unlike alkyd paints, acrylic paints are made on the basis of acrylic, a polymer better known as plexiglass. Paints may contain various additional components designed to improve certain properties (add elasticity, speed up drying).
Basic properties
- Life time. Unlike alkyd paint, the surface of acrylic paint retains its original appearance much longer. It is advisable to renew alkyd paint about once a year, since oxygen and ultraviolet radiation intensively destroy the surface layer of paint. Acrylic coating, subject to surface preparation and paint application technology, can last from 8 (wood) to 20 (plaster) years.
- UV resistance. Acrylic practically does not change the properties of the surface film when exposed to sunlight, that is, it does not fade, does not turn yellow, and does not acquire a “matte” appearance. Alkyd compounds are not so reliable in this regard.
- Drying process. But the alkyd film dries relatively quickly, and after just a couple of days it fully performs its protective and decorative functions. The acrylic film completes its formation approximately a month after application to the surface. In this case, the coating should be protected from mechanical influences until it is completely dry.
- Mechanical stability. The longer process of forming an acrylic film is compensated by a higher level of resistance to mechanical stress (deformation, scratches).
- Decorative properties. Alkyd compositions are distinguished by a more diverse range of shades and halftones, as well as generally brighter colors. On the other hand, acrylic paint lasts longer and does not require regular updating.
Are acrylic and alkyd paints compatible?
Is it possible to apply alkyd compounds to acrylic or vice versa? Neither of these is recommended, especially if the substrate was painted relatively recently or if the surface is metal. The fact is that the specific composition of the paints may not be completely clear to us. Alkyd compositions may contain components that will appear as dark spots through the acrylic paint layer. If alkyd paint is applied over acrylic, then it may not adhere to it, that is, it may peel off.
The only option for applying such paints to each other is to apply it to an old coating from which all the volatile components have already evaporated. However, even in this case, apply the top coat of paint only after treating the surface with a similar type of primer (that is, acrylic paint on acrylic primer and vice versa).
An ordinary consumer, far from construction, may encounter certain difficulties when choosing paint. Modern market offers big choice paint and varnish materials – which one to prefer? Some of the most popular paints and varnishes are alkyd and acrylic dyes. Many people scare them. Let's find out how alkyd paint differs from acrylic paint, and what you need to choose for a quality result.
Alkyd paints are a modern version of classic oil paints. Both alkyd and oil-based materials have a similar curing process. The paint is made on the basis of alkyd resin, which is obtained by processing vegetable oils under the influence of high temperature with the addition of various polyhydric alcohols. The composition of alkyd paint is clear from its name. Alkyd is alcohol or alcohol, and “acid” is acid.
For sale, these materials are supplied already containing solvents. Depending on the type of alcohol, paints can be divided into pentaphthalic and glyphthalic. Traditional white spirit, orthoxylene, nefras can be used as solvents for these paints.
Acrylic paint is produced on the basis of polyacrylic polymers. Acrylic is plexiglass, which is produced by the hydrolysis of lactic acids. Acrylic paints can be water-based or varnish-based. To obtain high elasticity and resistance to external influences environment and mechanical stress, the composition includes various additives and fillers.
As you can see, both paints differ from each other in composition. But there are other differences.
Characteristics and application features
The biggest difference between acrylic and alkyd paint is that the former is a material of natural origin, while the latter is a completely synthetic product.
Alkyd paint can be used in any way - it is a universal dye that can be applied to surfaces made of metal, wood, and stone. You may or may not use soil.
These dyes create a much harder, but less elastic film when compared with oil analogues. More often, this type of paintwork is used for interior finishing work, when it is necessary to obtain a durable surface with expressive and rich colors and a glossy sheen. Alkyd dye is often used as wood paint.
Acrylic paint is characterized by lower brightness and a matte effect. The market offers a huge range of these coatings. They are suitable for both artwork, and for work on internal and exterior decoration. Acrylic adheres well even to rust. Differences in resistance to environmental influences - acrylic materials widely used for finishing works of facades. You can often find acrylic auto enamel and primer.
On video: acrylic paints.
Advantages and disadvantages
Among the advantages of alkyd-based coloring materials are:
- Fast drying speed;
- Resistance to moisture and household chemicals;
- Ease of application;
- Affordable price;
- Large selection of colors and shades.
Polymerization begins 60 minutes after finishing painting work. The coating will reach maximum hardness in a few days. To apply alkyd-based paints, you do not need to be a professional painter or have professional tools and devices. Among the disadvantages is low durability - if the surface is used very intensively, and the layer is exposed to ultraviolet radiation, then within a few years the coating will begin to turn yellow. At the moment of evaporation, the components emit a rather specific odor. To obtain a high-quality result, preparatory work and a primer are needed.
The group of acrylic dyes is capable of significantly better maintaining strength and aesthetic characteristics even when exposed to high temperatures. Due to this property of acrylic, paints are widely used for painting heating radiators and other structures exposed to heat. Due to the fact that the material has good adhesion, the paint adheres well to wood - up to 8 years. When painting metal or plastered walls, the service life is up to 10 years. Also among the advantages are:
- Resistance to UV radiation, which is very important for exterior decoration;
- Transparency;
- Good hiding power and low consumption;
- Vapor permeability.
These dyes take between 30 minutes and 2 hours to dry completely. But it will take much more time to reach the final density. If the composition contains additives that protect against corrosion, then you can paint the metal even over rust. Among the disadvantages are the cost, the need to use solvents, and in some cases the need for primer.
Despite the disadvantages, acrylic materials are better than alkyd ones. Longer service life, coating more resistant to various influences.
The difference is that alkyd products are not suitable for outdoor use, while acrylic is ideal for outdoor use.
Compatibility
Knowing the differences between alkyd paint and acrylic paint, you should also learn about the compatibility of these two paints. Many people are interested in the question of whether it is possible to apply a layer of alkyd paint on top of acrylic paint.
It must be said that the compatibility of the two products is not very good. This is due to the composition of the materials. If you combine them, there is a risk of surface swelling. If you apply acrylic to alkyd, the result will not be good - the coating will begin to delaminate. But if there is a serious need to combine these different products, then you need to clean the surfaces as much as possible, then carefully sand them and apply primer. This will help improve adhesion and reduce the risk of peeling, but the service life is reduced by about half.
What's better?
So. Acrylic and alkyd paints have different composition, different properties. Let's try to find out which one is better. It really depends on the usage. If it is necessary to finish the facade, then acrylic. When painting a car, you should also give preference to acrylic-based enamels. With a small budget interior decoration You can also stop at alkyd paints.
Consumers are often faced with a choice: which paint to prefer - acrylic or alkyd? To answer this question, it is necessary to understand the features of these compositions, their advantages and disadvantages.
Alkyd paints
Alkyd paints and varnishes(LMB) can be classified as an advanced variety oil compositions. Alkyd paints have the same mechanism of hardening and film formation. Moreover, the film turns out to be more durable, although not so elastic. To correct the lack of elasticity, natural oils are added to alkyd mixtures.
The composition of alkyd paints and varnishes includes polyhydric alcohols (for example, propane-1,2,3-triol, otherwise called glycerin), as well as orthophthalic acid. The word “alkyd” itself is a construction formed from the combination of the words “alcohol” (alcohol) and “acid” (acid). Depending on the type of alcohol component, alkyd coatings are divided into pentaphthalic and glyphthalic.
Alkyd paints are one of the most common types of paints and varnishes, and there are many reasons for this:
- Low cost is perhaps the main advantage of alkyd compositions. The availability of paint is especially important if you have a limited budget or need to paint large surfaces.
- Working with alkyd coatings is simple: you don’t need any special instructions, and all the work can be done independently. The composition is diluted with an organic solvent and applied with a brush or roller.
- The coating dries quite quickly, with initial polymerization occurring after about 60 minutes. Complete drying occurs within a few days. The dried surface is ready for use in unfavorable environments.
- Alkyd coatings are resistant to moisture.
- Coatings are neutral to aggressive chemicals(for example, household chemicals).
Disadvantages of alkyd compositions:
- Insufficient wear resistance and resistance to mechanical stress. The durability of alkyd coatings leaves much to be desired: usually within a year and a half the surface turns yellow and begins to crack. As a result, the product will have to be painted too often. Sometimes similar disadvantage can be ignored, but in most cases for important surfaces it is better to choose a different type of paint.
- Instability to ultraviolet radiation, which is why the coating soon begins to fade and crack. For this reason, alkyd paints are not recommended for finishing facades.
- Alkyd mixtures contain harmful substances to human health chemical elements. In addition, freshly painted surfaces emit a pungent odor that disappears in at least a day.
- Not a very rich range of colors. This disadvantage can be corrected by purchasing the correct color scheme.
- Insufficient fire safety.
Acrylic paints
Polyacrylic polymers serve as the base in acrylic compositions. Acrylic paints and varnishes are made on the basis of a polymer, which is also called plexiglass. Special components are added to the composition to improve certain characteristics of the paint, for example, its elasticity, resistance to environmental factors or drying speed.
Advantages of acrylic compositions:
- Acrylates retain their characteristics even at elevated temperatures. Resistance to high temperatures allows the use of paintwork materials of this group when painting radiators and other surfaces exposed to heating. Acrylic paints not only do not crack under the influence of rising temperatures, but also do not change the original color.
- Acrylic compositions are characterized by excellent adhesion (the ability to grasp foreign surfaces).
- Exploitation acrylic coatings can be carried out for at least 8 years in the case of wood and at least 20 years for plastered and metal products.
- Acrylates are resistant to ultraviolet radiation, which means they are excellent for facade works. Acrylic exterior surfaces retain their original appearance for many years.
- Due to their high transparency and lack of yellowing of the coating, acrylic paints and varnishes are used for painting light types of wood. The acrylic group is also used in conjunction with pastel-colored stains.
- Acrylic paints and varnishes are non-toxic (unlike alkyd paints), since they do not contain organic solvents. To dissolve acrylic composition is suitable plain water.
- The paint does not contain hazardous components; as it dries, water evaporates. Therefore, there is no need for protective clothing when painting.
- Due to the absence of toxic solvents, acrylic paints and varnishes have no pungent odor and are suitable for interior work.
- Acrylic mixtures protect coatings from corrosive processes, and the presence of special additives in them allows you to paint even rusty surfaces.
- The acrylic group is characterized by high fire safety.
- With low paint consumption, high hiding power is ensured.
- Surfaces painted with acrylic paints and varnishes are able to “breathe”. Natural ventilation is extremely useful for preserving performance qualities wood products.
- Acrylic paints dry very quickly - it takes from half an hour to a couple of hours to dry the surface (the specific time depends on the conditions environment and solution components). Fast drying is a serious advantage when it comes to tight deadlines to carry out construction work.
- If paint gets into an unwanted place, it can be easily removed without damaging the surface.
Disadvantages of acrylic compositions:
- Relatively high cost.
- Insignificant dry residue. This figure usually does not exceed 30%.
- The coating takes quite a long time to gain strength. Final hardening occurs no earlier than 30 days.
Paint compatibility
Acrylic paints are not recommended for use on alkyd coatings, since the result of painting in this case cannot be predicted. After painting, the surface may look like good quality, and bad (if bloating occurs). Alkyd paints and enamels applied to acrylic surfaces, in most cases will peel off.
Please note: if acrylic paint is applied to an alkyd coating, its service life is reduced by at least 2 times.
If you still need to apply acrylic paints and varnishes to the alkyd coating, the surface needs to be prepared. First, the product should be thoroughly cleaned with fine-grained sandpaper and then treated with primer. Preparatory activities will improve the adhesion of materials and reduce the likelihood of paint peeling.
There are alkyd-acrylic compositions used for painting vehicles. However, their cost is high, and such paints are not used in the construction field.
So, based on the totality of qualities the best choice- acrylic paint. However, if the budget is limited or the durability of the coating is not critical, you can opt for alkyd paint.